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Unmatched ssd create huge unuseful iostat output

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Operating Systems Solaris Unmatched ssd create huge unuseful iostat output
# 1  
Old 03-19-2015
Unmatched ssd create huge unuseful iostat output

My scheduled collection of statistics is giving very large output because of an high number of ssd device not associated to any disk
The iostat -x command is collecting statistics from them and the output is very large.

if a run
iostat -x|tail +3|awk '{print $1}'>f0.txt.$$
iostat -nx|tail +3|awk '{print "/dev/dsk/"$11}'>f1.txt.$$
paste -d= f[01].txt.$$ > assoc.txt

then in assoc.txt I find not only rows like

but also many rows as

an the output is plenty of statistics about device that not really exists

iostat -x ssd3220
                 extended device statistics
device     r/s    w/s   kr/s   kw/s wait actv  svc_t  %w  %b
ssd3220    0.0    0.0    0.0    0.0  0.0  0.0    0.0   0   0

How can I delete such ssd ?

Last edited by Franklin52; 03-19-2015 at 09:21 AM.. Reason: Please use code tags
# 2  
Old 03-21-2015
use the -z option. This example assumes those dummy devices do no I/O and you do not want the first "run" of iostat which shows activity averaged over time since boot:

iostat -zx 2 5 | awk '/svc_t/ {cnt++} cnt>1' > file2keep

Otherwise create a file that lists the ones you do not want:

iostat -x | grep -vf excludefile

Example excludefile:

This User Gave Thanks to jim mcnamara For This Post:
# 3  
Old 03-21-2015
You might want to clean the disk device map with:
devfsadm -C -c disk -v

These 2 Users Gave Thanks to jlliagre For This Post:
# 4  
Old 03-23-2015
It's useful, but I cannot change collecting scripts

---------- Post updated at 01:46 PM ---------- Previous update was at 01:44 PM ----------

I've already changed device map with devfsadm, but dummy devices are still there
# 5  
Old 03-23-2015
So you are saying that you have giant input files, and cannot do anyhting change how they are created. That would have been nice to know earlier.

1. generate a list of ssd devices that are useless to you. Call the file exclude.txt
2. use nawk on the two files, exclude.txt and giant.txt
nawk 'FILENAME=="exclude.txt" {arr[$0]=1;next}
         FILENAME=="giant.txt" { if($1 in arr) 
                                              {print $0}
          }   '  exclude.txt giant.txt   > reportfile

Note: the order of file names on the command is required: exclude.txt comes first.
# 6  
Old 03-23-2015
I'm afraid I can't apply this workaround
giant ouput files are not in ascii format (it's the output of sadc command)
what I'm looking for is a way to exclude such ghost devices from any system check (without restarting the system)

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